my_dict = {"江城": 99, "叶君临": 100, "陈凡": 98}
print(my_dict)
# 嵌套字典
my_dict1 = {"江城": {"语文": 99,
                     "数学": 100},

            "叶君临":
                {"数学": 100,
                 "语文": 45}}
print(my_dict1)
print(my_dict1["江城"]["语文"])
# 删除字典元素
m = my_dict.pop("江城")
print(m)
keys = my_dict.keys()
print(keys)
for x in my_dict:
    print(x)